View source for Canadian Shield

== Ecology ==
<!---not quite ready to delete this yet, but it does not seem germane to geology. Definitely of use to a GEOGRAPHY article about the same area--->
The current [[geomorphology|surface expression]] of the Shield is one of very thin soil lying on top of the [[bedrock]], with many bare outcrops. This arrangement was caused by severe [[glacier|glaciation]] during the [[Quaternary glaciation|ice age]], which covered the Shield and scraped the rock clean.

The lowlands of the Canadian Shield have a very dense soil that is not suitable for forestation, but it also contains many marshes and bogs. The rest of the region has coarse soil that does not retain moisture well and is frozen with [[permafrost]] year round. Forests are not as dense in the north.

The Shield is covered in parts by vast [[boreal forest]]s in the south that support natural [[ecosystem]]s as well as a major [[logging]] industry. This boreal forest area includes ecoregions such as the [[Eastern Canadian Shield taiga]] that covers northern Quebec and most of Labrador, and the [[Midwestern Canadian Shield forests]] that run westwards from [[Northwestern Ontario]]. [[Hydrography|Hydrographical]] drainage is generally poor, the effects of [[glaciation]] being one of the many reasons. [[Tundra]] typically prevails in the northern regions. Many mammals such as [[caribou]], [[white-tailed deer]], [[moose]], [[Gray wolf|wolves]], [[wolverine]]s, [[weasel]]s, [[mink]], [[otter]]s, [[grizzly bear]], [[polar bear]]s and [[American black bear|black bears]] are present.<ref>{{NatGeo ecoregion|id=na0612|name=Northern Canadian Shield taiga}}</ref> In the case of polar bears (''Ursus maritimus'') the Shield area contains many of the [[Maternity den|denning]] locations such as the [[Wapusk National Park]].<ref>C. Michael Hogan (2008) [http://globaltwitcher.auderis.se/artspec_information.asp?thingid=36084 ''Polar Bear: Ursus maritimus'', Globaltwitcher.com, ed. Nicklas Stromberg]</ref>